Harvard-trained nutrition expert: If I could only prioritize one food in my diet, it'd be this

Meat is good for you. There are experts who might disagree with me, and many researchers continue to search for evidence linking meat to heart disease, for example.

But as a Harvard-trained, board-certified psychiatrist specializing in nutritional and metabolic psychiatry, I've long been curious about the relationship between food and brain health, as well as overall well-being. And in my research, I've yet to find a credible, plausible health argument against eating meat of any kind (including red meat, seafood, and poultry).

In fact, no other food group is nutritious enough, safe enough, or geographically accessible enough to recommend as the healthy foundation of the optimal human diet. 

So if I could only afford to buy food from one food group, I'd prioritize meat.

Meat is good for gut health because it's non-irritating, easy to digest, and supports healthy insulin levels without promoting blood glucose spikes.

It also provides all of the macronutrients and micronutrients we need, including some that are difficult or impossible to obtain from plant foods. For instance, it's an excellent source of every B vitamin, including B7, which plants contain very little of, and B12, which plants do not contain at all.

Only meat contains heme iron, a form of iron at least three times easier for us to absorb than the non-heme iron in plants. And only animal-source foods contain the MK‑4 form of vitamin K2, which is easier to absorb (and is the form used by the human brain).

Some scientists even argue that eating meat made us human — meaning that it allowed us to devote less energy and bodily real estate to the long intestinal tract needed to process high-fiber, high-plant diets, so that we could invest more energy in developing our uniquely oversized brains.

Here's how to incorporate meat in your diet the right way: 

• Choose healthy meats. Whenever possible, choose meats from wild animals or animals that have been raised humanely, allowed ample access to the outdoors, and fed a species-appropriate diet.
• Don't let the perfect be the enemy of the good. If you can't access or afford high-quality meat, just do the best you can. 
• It doesn't have to be red meat. Shellfish, fatty fish, duck, and poultry liver are all highly nutritious alternatives to red meat (meat of mammals).
• Eat fresh. Choose unprocessed fresh (or freshly frozen) meats whenever possible. 
• Don't fear natural animal fats. Fattier cuts of meat are more flavorful, more nutritious, and often less expensive. Unfortunately, pork and poultry fat from conventionally-raised animals can be high in linoleic acid, a fragile omega-6 fatty acid with a tendency to degrade into toxic byproducts that can cause damaging oxidative stress throughout the brain and the rest of the body.
• Cook gently. Don't overcook meat, as this will damage nutrients and flavor. Trim away any burned or blackened areas of meats grilled or cooked at high temperatures. 
• Think about your protein goal. While protein targets vary depending on age, ideal body weight, health status, activity level, and other factors, most adult requirements fall somewhere between 0.6 and one gram of protein per pound of ideal body weight. For example: A woman whose ideal body weight is 125 pounds would require at least 75 grams of protein per day — roughly the amount found in one pound of 85% lean ground beef (which contains just over five grams of protein per ounce).
• Don't overdo it. Overeating protein can promote higher insulin levels (and even slightly higher glucose levels in some people). 

There are plenty of unanswered questions about nutrition, but I'd say the answer to "Does meat belong in the human diet?" is a resounding yes.

Georgia Ede, MD, is a Harvard-trained psychiatrist specializing in nutrition science and brain metabolism. Her 25 years of clinical experience include 12 years as a psychiatrist and nutrition consultant at Smith College and Harvard University Health Services. She is also the author of "Change Your Diet, Change Your Mind." 

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This is an adapted excerpt from "Change Your Diet, Change Your Mind: A Powerful Plan to Improve Mood, Overcome Anxiety, and Protect Memory for a Lifetime of Optimal Mental Health." Copyright © 2024, Dr. Georgia Ede. Reproduced by permission of Balance. All rights reserved.